replace string16 with StringPiece16 in ConvertUTF16ToJavaString()

base/android/jni_string.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_ANDROID_JNI_STRING_H_
 #define BASE_ANDROID_JNI_STRING_H_
 
 #include <jni.h>
 #include <string>
 
 #include "base/android/scoped_java_ref.h"
-#include "base/string16.h"
 #include "base/string_piece.h"
 
 namespace base {
 namespace android {
 
 // Convert a Java string to UTF8. Returns a std string.
 std::string ConvertJavaStringToUTF8(JNIEnv* env, jstring str);
 std::string ConvertJavaStringToUTF8(const JavaRef<jstring>& str);
 
 // Convert a std string to Java string.
 ScopedJavaLocalRef<jstring> ConvertUTF8ToJavaString(
-    JNIEnv* env, const base::StringPiece& str);
+    JNIEnv* env,
+    const base::StringPiece& str);
 
 // Convert a Java string to UTF16. Returns a string16.
 string16 ConvertJavaStringToUTF16(JNIEnv* env, jstring str);
 string16 ConvertJavaStringToUTF16(const JavaRef<jstring>& str);
 
 // Convert a string16 to a Java string.
 ScopedJavaLocalRef<jstring> ConvertUTF16ToJavaString(
-    JNIEnv* env, const string16& str);
+    JNIEnv* env,
+    const base::StringPiece16& str);
 
 }  // namespace android
 }  // namespace base
 
 #endif  // BASE_ANDROID_JNI_STRING_H_